Some languages arrive with much publicity, often to then stall, while others quietly get on with a job and steadily spread till you can't help but notice them. Lua is a language from the latter category, mainly because it was designed to be embedded and to not draw attention to itself by chewing up resources.

But when you find open source projects such as VLC, Wireshark, Nginx and Celestia and commercial software such as Adobe Photoshop Lightroom using Lua as the basis for scripting in the applications, and it starts picking up awards because it's achieved critical mass in particular industries, it is worth finding out a little more about the language and why it is appearing as part of these applications.

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You don't need to be a genius to debug a pf.conf firewall ruleset, you just need the guts to run tcpdump